The present invention relates to a stator coil support device of an electric rotating machinery wherein an elastic member is inserted between a stator coil and a wedge.
In the most recent electric rotating machineries such as turbine generators, it becomes possible to increase capacity (output) thereof, as compared with the prior art, in accordance with the progressing of cooling technology.
However, increasing capacity of turbine generators has brought about an abrupt increase in a current flowing in the stator coil. Consequently, electromagnetic vibrations of double frequency are generated in the slot of the stator core in which the stator core is installed during a normal operation, and in the event of an abnormal operation at a time, for example, when a short circuiting or like occurs, excessive transient electromagnetic force is generated.
In a conventional turbine generator, such abnormal phenomenon has been dealt with by adopting a structure shown in FIGS. 16 to 19 for the stator coil support device.
With reference to FIGS. 16 to 19, in the stator coil support device, a stator coil 3 is installed in a slot 2 of a stator core 1 constituted by superimposing thin sheets, for example, sheets of silicon steel, along an axial direction thereof and, at one end of the stator coil 3 installed in the slot 2, as shown by way of example in FIGS. 16 to 18, the slot 2 has an opening which is closed by a wedge 6 having inclined surfaces, with an elastic plate 4 and a sliding plate 5 formed with an inclined shape being inserted. The elastic plate 4 is called a ripple spring formed as an undulating (wave-shaped) laminated plate formed through a hot press forming process of a thermosetting resin such as phenol or epoxy resin with cotton or glass cloth etc being as base material. The electromagnetic vibrations generated during the operation are arranged to be suppressed by skillfully utilizing the elastic force due to the undulations of the elastic plate 4.
Further, in a conventional stator coil support device, the electromagnetic vibrations are suppressed in the same way as described above by mounting the elastic plate 4 as shown in FIG. 18 also on the side surface of the stator coil 3 shown in FIG. 16 with an insulating layer, not shown, being inserted.
In this way, in a conventional stator coil support device, the electromagnetic vibrations have been suppressed, and a damage to the insulating layer has been prevented by the elastic force of the undulation (wave-shape) of the elastic plate 4 which is inserted in the gap between the wedge 6 and the stator coil 3 installed in the slot 2 of the stator core 1 and, in addition, the electrical loss or like that accompanies the formation of the gap has been also prevented.
Although the prior art stator coil support device shown in FIGS. 16 to 19 is excellent in the point of well suppressing electromagnetic vibrations generated in the slot of the stator core, the prior art still provided the following problems.
In order to suppress vibrations of the stator coil 3, the conventional stator coil support device requires the elastic plate 4, the sliding plate 5 and the wedge 6, as described above.
However, if the structural components of the stator coil support device become large in number, the time required for assembling the components increases and more time is spent in the assembling operation, which has repercussions on costs, leading to a problem of high cost. In particular, in regard to the structural components employed in the stator coil support device, it is required for a worker to make simple the operation due to the fact that the assembling operation is generally performed in a restricted location.
An object of the present invention is to substantially eliminate defects or drawbacks encountered in the prior art mentioned above and to provide a stator coil support device for an electric rotating machinery (rotary electric machine) in which simplification of the assembling operation is achieved by reducing the number of structural components.
This and other objects can be achieved according to the present invention by providing, in one aspect, a stator coil support device for an electric rotating machinery, comprising:
a stator core provided with a slot having an opening;
a stator coil installed in the slot of the stator core;
a wedge member disposed so as to close the opening of the slot of the stator core; and
an elastic member inserted between the stator coil and the wedge member,
wherein the wedge member is formed so as to have an inclination towards an axial direction of the stator core and the elastic member has a structure undulating towards the axial direction.
In another aspect, there is provided a stator coil support device for an electric rotating machinery, comprising:
a stator core provided with a slot having an opening;
a stator coil installed in the slot of the stator core;
a wedge member disposed so as to close the opening of the slot of the stator core; and
an elastic member inserted between the stator coil and the wedge member,
wherein the wedge member is formed so as to have an inclination towards an axial direction of the stator core, the elastic member has a recess, in cross-section, at a central portion thereof, and flanges are provided on both sides of the recess in an inclined manner towards the axial direction.
In a further aspect, there is also provided a stator coil support device for an electric rotating machinery, comprising:
a stator core provided with a slot having an opening;
a stator coil installed in the slot of the stator core;
a wedge member disposed so as to close the opening of the slot of the stator core; and
an elastic member inserted between the stator coil and the wedge member,
wherein the wedge member is formed so as to have an inclination towards an axial direction of the stator core and the elastic member is formed as a split cylinder structure having an inclination towards the axial direction of the stator core.
In a still further aspect, there is also provided a stator coil support device for an electric rotating machinery, comprising:
a stator core provided with a slot having an opening;
a stator coil installed in the slot of the stator core;
a wedge member disposed so as to close the opening of the slot of the stator core; and
an elastic member inserted between the stator coil and the wedge member,
wherein the wedge member is formed so as to have an inclination towards an axial direction of the stator core and the wedge member is formed so as to have an inclination towards the axial direction and provided with ratches on the inclined side, and wherein the elastic member has a plate structure having a recess, in a cross-section, at a central portion thereof, flanges are provided on both sides of the recess and ratches are provided on the flanges, which are formed in an inclined manner towards the axial direction.
In a still further aspect, there is provided a stator coil support device for an electric rotating machinery, comprising:
a stator core provided with a slot having an opening;
a stator coil installed in the slot of the stator core;
a wedge member disposed so as to close the opening of the slot of the stator core; and
an elastic member inserted between the stator coil and the wedge member,
wherein the elastic member has a recess, in cross section, into which said wedge member is fitted.
In a still further aspect, there is also provided a stator coil support device for an electric rotating machinery, comprising:
a stator core provided with a slot having an opening;
a stator coil installed in the slot of the stator core;
a wedge member disposed so as to close the opening of the slot of the stator core; and
an elastic member inserted between the stator coil and the wedge member,
wherein the elastic member is provided with a recess, in cross-section, which is formed with a side to be engaged with a groove formed to the wedge member.
In a still further aspect, there is also provided a stator coil support device for an electric rotating machinery, comprising:
a stator core provided with a slot having an opening;
a stator coil installed in the slot of the stator core;
a wedge member disposed so as to close the opening of the slot of the stator core; and
an elastic member inserted between the stator coil and the wedge member,
wherein the stator coil in the slot of the stator core is covered by the elastic plate with said wedge interposed therebetween, the elastic member is provided with a recess, in cross-section, and flanges are provided on both sides of the recess to be engaged with a groove formed to both slot sides of the stator core.
In preferred embodiments of some of the above aspect, the elastic member has a plate structure having at least one wave-peak, and in a certain case, the elastic member has a plurality of wave-peaks which have heights gradually increasing along the axial direction of the stator core.
The wedge member has an inclination towards the axial direction of the stator core in a range of not less than 0xc2x0 but not more than 10xc2x0. The elastic member has a plate structure having an inclination towards the axial direction of stator core in a range of not less than 0xc2x0 but not more than 10xc2x0.
The recess is formed in a trapezoidal shape. The wedge member is formed in a polygonal shape so as to be fitted into the recess formed in the elastic member by utilizing sides of the polygonal shape.
The elastic member has a plate structure made of glass fiber reinforced plastic material. The elastic member has a plate structure made of non-magnetic stainless-steel material.
According to the stator coil support device for the electric rotating machinery according to the present invention of the aspects and characters mentioned above, the stator coil installed in the slot of the stator core can be supported by the wedge with the elastic plate being inserted. Therefore, the number of structural components can be reduced, so that the assembling operation can be facilitated, thus making it possible to shorten the time required for the assembling operation compared with the conventional technology.
The nature and further characteristic features of the present invention will be made more clear from the following descriptions made with reference to the accompanying drawings.